As mobile device technology continues to develop and demand therefor continues to increase, demand for secondary batteries as energy sources is rapidly increasing. Among these secondary batteries, research on lithium secondary batteries, which exhibit high energy density and discharge voltage, is underway and such lithium secondary batteries are commercially available and widely used.
In general, secondary batteries have a structure in which an electrode assembly including a positive electrode, a negative electrode, and a separator disposed therebetween is accommodated in a laminated or wound form in a battery case made of a metal can or a laminate sheet and an electrolyte is injected thereinto or the electrode assembly is impregnated with an electrolyte.
As a positive electrode active material of such secondary batteries, Mn-rich positive electrode active materials are used. However, Mn-rich active materials contain a large amount of Mn—O, and thus, have low conductivity. Accordingly, batteries including Mn-rich active materials have low output, much lower output at low temperature.
Therefore, there is an urgent need to develop a novel electrode and lithium secondary battery that address the problems described above.